Chemically modified fullerene derivatives are of great interest as electron acceptors in organic photovoltaics.1 The vast majority of derivatives synthesized and employed so far are based on the 1,2 addition on a 6 member ring. The 1,2 addends class include [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)2 and thio-PCBM,3 which are commercial products, its azoanalogues4 and a variety of other derivatives bearing different functional groups.1 Previous reports on fullerene derivatives employed in solar cells demonstrated that small and subtle modifications of the appended functionalities can lead to dramatic and often unpredictable changes in the performance of the device.1 Nevertheless, most of the attempted studies, with few exceptions,5 brought to a decreased efficiency when compared to that one of PCBM.